Step 1: Identify the tense and structure of the passive sentence. “is made” is the Simple Present Passive. The object is 'Butter', and the subject (agent) is 'us'.
Step 2: Convert to active voice. The subject of the passive sentence ('us') becomes the subject of the active sentence ('We'). The object ('Butter') moves after the verb.
Step 3: Change the verb form. The Simple Present Passive ('is made') changes to the Simple Present Active. For the subject 'We', the correct form is 'make'.
Step 4: Construct the final sentence. The resulting active sentence is: "We make butter from milk."